U.S. patent number 9,239,125 [Application Number 14/627,341] was granted by the patent office on 2016-01-19 for manifold assembly with multiple articulating arm assemblies.
This patent grant is currently assigned to FMC Technologies, Inc.. The grantee listed for this patent is FMC Technologies, Inc.. Invention is credited to Paul A. Crawford, William H. Garner, James R. Soltau, Tep Ungchusri.
United States Patent |
9,239,125 |
Ungchusri , et al. |
January 19, 2016 |
Manifold assembly with multiple articulating arm assemblies
Abstract
A manifold assembly for connecting a plurality of pumping units
to a wellhead includes at least one main line which is connectable
to the wellhead and includes a plurality of discharge connectors,
and a plurality of articulating arm assemblies which are each
connected to a corresponding discharge connector. Each arm assembly
comprises a connector member which includes at least an inlet port,
an outlet port and a third port that is located generally opposite
the outlet port and is closed by a removable plug member, an
articulating conduit assembly which comprises a first end that is
connected to the inlet port and a second end that is connectable to
a corresponding one of the plurality of pumping units, and a riser
swivel which is connected between the outlet port and the discharge
connector. In use of the manifold assembly, each arm assembly is
connected to a corresponding pumping unit and the main line is
connected to the wellhead to thereby connect the pumping units to
the wellhead.
Inventors: |
Ungchusri; Tep (The Woodlands,
TX), Garner; William H. (Houston, TX), Crawford; Paul
A. (Houston, TX), Soltau; James R. (Stephenville,
TX) |
Applicant: |
Name |
City |
State |
Country |
Type |
FMC Technologies, Inc. |
Houston |
TX |
US |
|
|
Assignee: |
FMC Technologies, Inc.
(Houston, TX)
|
Family
ID: |
47506769 |
Appl.
No.: |
14/627,341 |
Filed: |
February 20, 2015 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20150159795 A1 |
Jun 11, 2015 |
|
Related U.S. Patent Documents
|
|
|
|
|
|
|
Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
|
14129006 |
|
9004104 |
|
|
|
PCT/US2011/001194 |
Jul 8, 2011 |
|
|
|
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F17D
1/08 (20130101); F16L 41/18 (20130101); E21B
43/26 (20130101); Y10T 137/8807 (20150401) |
Current International
Class: |
E03B
1/00 (20060101); E21B 43/26 (20060101); F17D
1/08 (20060101); F16L 41/18 (20060101) |
Field of
Search: |
;137/615 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Lee; Kevin
Attorney, Agent or Firm: Query, Jr.; Henry C.
Claims
What is claimed is:
1. A manifold assembly for connecting a plurality of pumping units
to at least one wellhead, the manifold assembly comprising: at
least one main line which is connectable to the wellhead, said main
line including a plurality of discharge connectors; a plurality of
articulating arm assemblies which are each connected to a
corresponding discharge connector, each arm assembly comprising: a
connector member which includes at least an inlet port, an outlet
port and a third port that is located generally opposite the outlet
port and is closed by a removable plug member; an articulating
conduit assembly which comprises a first end that is connected to
the inlet port and a second end that is connectable to a
corresponding one of said plurality of pumping units; and a riser
swivel which is connected between the outlet port and the discharge
connector; whereby in use of the manifold assembly each arm
assembly is connected to a corresponding pumping unit and the main
line is connected to a wellhead to thereby connect the pumping
units to the wellhead.
2. The manifold assembly of claim 1, wherein the third port is
positioned vertically above the inlet and outlet ports.
3. The manifold assembly of claim 2, wherein the manifold assembly
is configured such that the third port is positioned vertically
above the conduit assembly when the second end is connected to the
pumping unit.
4. The manifold assembly of claim 2, further comprising a choke
insert which is positioned in the outlet port and is removable
through the third port.
5. The manifold assembly of claim 4, wherein the choke insert is
supported on a seal assembly which is positioned between the
connector member and the riser swivel.
6. The manifold assembly of claim 4, wherein the choke insert
extends through the third port to the plug member.
7. The manifold assembly of claim 6, wherein the choke insert is
connected to the plug member.
8. The manifold assembly of claim 4, wherein the choke insert
includes at least one inlet opening and the arm assembly further
comprises means for aligning the inlet opening with the inlet
port.
9. The manifold assembly of claim 4, wherein the plug member
comprises a blind nut and the choke insert comprises a radial
flange which is trapped between the blind nut and an adjacent
portion of the connector member to thereby secure the choke insert
within the connector member.
10. The manifold assembly of claim 1, wherein the connector member
comprises a fourth port which is located generally opposite the
inlet port and is closed by a second removable plug member.
11. The manifold assembly of claim 10, wherein the connector member
is configured such that each of the inlet port and the fourth port
is connectable to the conduit assembly.
12. The manifold assembly of claim 11, further comprising a choke
insert which is positioned in the inlet port and is removable
through the fourth port.
13. The manifold assembly of claim 12, wherein the choke insert is
positioned against a seal assembly which is positioned between the
connector member and the conduit assembly.
14. The manifold assembly of claim 12, wherein the choke insert
extends through the fourth port to the second plug member.
15. The manifold assembly of claim 14, wherein the choke insert is
connected to the second plug member.
16. The manifold assembly of claim 4, wherein: the choke insert
includes a choke orifice which comprises an exit opening diameter
at an end of the choke orifice adjacent the riser swivel; the riser
swivel includes a male swivel part which comprises a male swivel
bore and a female swivel part which comprises a female swivel bore;
and the diameter of at least one of the male swivel bore and the
female swivel bore increases from a first diameter approximately
equal to the exit opening diameter to a second, larger diameter to
thereby create a pressure drop in a fluid flowing through the riser
swivel.
17. The manifold assembly of claim 4, wherein: the choke insert
includes a choke orifice which comprises an exit opening diameter
at an end of the choke orifice adjacent the riser swivel; the riser
swivel includes a male swivel part which comprises a male swivel
bore and a female swivel part which comprises a female swivel bore;
the female swivel part is located adjacent the choke insert; the
diameter of the female swivel bore increases from a first diameter
approximately equal to the exit opening diameter to a second,
larger diameter; and the diameter of the male swivel bore is
approximately equal to the second diameter.
18. The manifold assembly of claim 4, wherein: the choke insert
includes a choke orifice which comprises an exit opening diameter
at an end of the choke orifice adjacent the riser swivel; the riser
swivel includes a male swivel part which comprises a male swivel
bore and a female swivel part which comprises a female swivel bore;
the female swivel part is located adjacent the choke insert; the
diameter of the female swivel bore is approximately equal to the
exit opening diameter; and the diameter of the male swivel bore
increases from a first diameter approximately equal to the exit
opening diameter to a second, larger diameter.
19. The manifold assembly of claim 4, wherein the riser swivel is
connected to an isolation valve which in turn is connected to the
discharge connector.
20. The manifold assembly of claim 19, wherein: the choke insert
includes a choke orifice which comprises an exit opening diameter
at an end of the choke orifice adjacent the riser swivel; the riser
swivel includes a male swivel part which comprises a male swivel
bore and a female swivel part which comprises a female swivel bore;
the diameter of the male swivel bore is approximately equal to the
exit opening diameter; the diameter of the female swivel bore is
approximately equal to the exit opening diameter; and the isolation
valve includes a valve bore which comprises a diameter that
increases from a first diameter approximately equal to the exit
opening diameter to a second, larger diameter.
21. The manifold assembly of claim 19, wherein: the choke insert
includes a choke orifice which comprises an exit opening diameter
at an end of the choke orifice adjacent the riser swivel; the
isolation valve includes a valve bore and a closure member which is
positioned across the valve bore; the valve bore comprises a
diameter which is larger than the exit opening diameter; and the
closure member includes a closure member bore which comprises an
orifice having a diameter which is approximately equal to the exit
opening diameter.
22. A manifold assembly for connecting a plurality of pumping units
to at least one wellhead, the manifold assembly comprising: at
least one main line which is connectable to the wellhead, said main
line including a plurality of discharge connectors; a plurality of
articulating arm assemblies which are each connected to a
corresponding discharge connector, each arm assembly comprising: a
connector member which includes at least an inlet port, an outlet
port and a third port that is located generally opposite the inlet
port and is closed by a removable plug member; an articulating
conduit assembly which comprises a first end that is connected to
the inlet port and a second end that is connectable to a
corresponding one of said plurality of pumping units; and a riser
swivel which is connected between the outlet port and the discharge
connector; whereby in use of the manifold assembly each arm
assembly is connected to a corresponding pumping unit and the main
line is connected to a wellhead to thereby connect the pumping
units to the wellhead.
23. The manifold assembly of claim 22, wherein the connector member
is configured such that each of the inlet port and the third port
is connectable to the conduit assembly.
24. The manifold assembly of claim 22, further comprising a choke
insert which is positioned in the inlet port and is removable
through the third port.
25. The manifold assembly of claim 24, wherein the choke insert is
positioned against a seal assembly which is positioned between the
connector member and the conduit assembly.
26. The manifold assembly of claim 24, wherein the choke insert
extends through the third port to the plug member.
27. The manifold assembly of claim 26, wherein the choke insert is
connected to the plug member.
28. The manifold assembly of claim 24, wherein the choke insert
includes at least one inlet opening and the arm assembly further
comprises means for aligning the inlet opening with the outlet
port.
29. The manifold assembly of claim 24, wherein the plug member
comprises a blind nut and the choke insert comprises a radial
flange which is trapped between the blind nut and an adjacent
portion of the connector member to thereby secure the choke insert
within the connector member.
30. A manifold assembly for connecting a plurality of pumping units
to at least one wellhead, the manifold assembly comprising: at
least one main line which is connectable to the wellhead, said main
line including a plurality of discharge connectors; a plurality of
articulating arm assemblies which are each connected to a
corresponding discharge connector, each arm assembly comprising: a
connector member which includes at least an inlet port and an
outlet port; an articulating conduit assembly which comprises a
first end that is connected to the inlet port and a second end that
is connectable to a corresponding one of said plurality of pumping
units; and a riser swivel which is connected between the outlet
port and the discharge connector; wherein each arm assembly defines
a flow bore extending between the connector member and the
discharge connector; and wherein said flow bore comprises a bore
section having a diameter which increases from a first diameter to
a second, larger diameter in a direction toward the discharge
connector to thereby create a pressure drop in a fluid flowing
through the flow bore; whereby in use of the manifold assembly each
arm assembly is connected to a corresponding pumping unit and the
main line is connected to a wellhead to thereby connect the pumping
units to the wellhead.
31. The manifold assembly of claim 30, wherein: the riser swivel
includes a male swivel part which comprises a male swivel bore and
a female swivel part which comprises a female swivel bore; and at
least one of the male swivel bore and the female swivel bore
comprises said bore section.
32. The manifold assembly of claim 30, wherein: the riser swivel is
connected to an isolation valve which in turn is connected to the
discharge connector; and the isolation valve includes a valve bore
which comprises said bore section.
33. The manifold assembly of claim 32, wherein the riser swivel
includes a male swivel part having a male swivel bore and a female
swivel part having a female swivel bore, and wherein at least one
of the male swivel bore and the female swivel bore comprises a
diameter which is approximately equal to the first diameter.
34. The manifold assembly of claim 30, wherein: the riser swivel is
connected to an isolation valve which in turn is connected to the
discharge connector; the isolation valve includes a valve bore and
a closure member which is positioned across the valve bore; and the
closure member includes a closure member bore which comprises said
bore section.
35. The manifold assembly of claim 34, wherein the riser swivel
includes a male swivel part having a male swivel bore and a female
swivel part having a female swivel bore, and wherein at least one
of the male swivel bore and the female swivel bore comprises a
diameter which is approximately equal to the first diameter.
36. The manifold assembly of claim 35, wherein at least one of the
male swivel bore and the female swivel bore comprises a second bore
section having a diameter which increases in a direction toward the
discharge connector to thereby create a pressure drop in a fluid
flowing through the flow bore.
Description
This application is based on and claims priority from U.S. patent
application Ser. No. 14/129,006 filed on Dec. 23, 2013, now U.S.
Pat. No. 9,004,104, which in turn is based on and claims priority
from International Patent Application No. PCT/US2011/001194 filed
on Jul. 8, 2011.
BACKGROUND OF THE INVENTION
The present invention is directed to a manifold assembly for
connecting a plurality of pumping units to a main line which in
turn is connectable to a wellhead or the like. More particularly,
the invention is directed to a manifold assembly which comprises a
plurality of articulating arm assemblies which are each connected
to the main line and extendable for connection to respective
pumping units.
High pressure well service pumping units are commonly used in the
hydrocarbon production industry to inject a variety of fluids into
an oil or gas well during certain well servicing operations. For
example, during a fracturing operation such pumping units are used
to inject a particle-containing slurry into the well in order to
fracture the hydrocarbon bearing formation and thereby produce
channels within the formation through which the oil or gas may
flow.
Typical fracturing operations require the use of several pumping
units operating in unison to inject a large volume of slurry into
the well. The pumping units are mounted on respective trucks or
trailers which are parked close together, and the discharge pipe
assembly of each pumping unit is connected to the so called main
line of a collection manifold which is located on a separate
manifold trailer.
The connection between each pumping unit and the main line is
usually made using a temporary flow line comprising a collection of
individual and pre-assembled pipes and swivel joints which are
secured together by clamps or connectors. The flow line components
are stowed on the truck or trailer in compact configurations, and
when the truck or trailer reaches the job site, they must be
unfolded and assembled in order to extend the flow line to the main
line. However, this operation is time consuming, especially when
multiple pumping units must be connected to the main line.
Also, in order to provide adequate support for the flow line, a
common practice is to run the flow line from the truck or trailer
to the ground and then from the ground to the collection manifold.
However, this requires that each flow line be made up of several
swivel joints comprising multiple swivel connections. In addition,
the parts of the flow line which rest on the ground can experience
undue wear that may shorten the life of these components.
Furthermore, the numerous components of the many flow lines create
cramped and cluttered conditions in the area between the pumping
units and the manifold trailer, which can be a safety hazard for
persons assembling the flow lines.
Furthermore, each flow line is typically connected to choke in
order to create a pressure drop in the fluid flowing through the
flow line and reduce pressure pulsations in the main line resulting
from operation of the pumping units. The choke usually includes a
fixed orifice choke insert which is mounted in a choke housing. The
choke housing is normally connected to an isolation valve which in
turn is connected to the main line. Thus, if the choke insert needs
to be replaced, the choke housing must usually be disconnected from
both the flow line and the isolation valve. Also, creating a
desired pressure drop over a single choke usually results in a
large amount of erosion in the isolation valve.
SUMMARY OF THE INVENTION
According to the present invention, these and other limitations in
the prior art are addressed by providing a manifold assembly for
connecting a plurality of pumping units to at least one wellhead.
The manifold assembly comprises at least one main line which is
connectable to the wellhead and includes a plurality of discharge
connectors, and a plurality of articulating arm assemblies which
are each connected to a corresponding discharge connector. Each arm
assembly comprises a connector member which includes at least an
inlet port, an outlet port and a third port that is located
generally opposite the outlet port and is closed by a removable
plug member; an articulating conduit assembly which comprises a
first end that is connected to the inlet port and a second end that
is connectable to a corresponding one of said plurality of pumping
units; and a riser swivel which is connected between the outlet
port and the discharge connector. In use of the manifold assembly
each arm assembly is connected to a corresponding pumping unit and
the main line is connected to the wellhead to thereby connect the
pumping units to the wellhead.
The present invention will now be described with reference to the
accompanying drawings. In the drawings, the same reference numbers
may be used to denote similar components in the various
embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a side elevation view of an illustrative embodiment of
the manifold assembly of the present invention shown mounted on a
truck trailer;
FIG. 1B is a top plan view of the manifold assembly of FIG. 1;
FIG. 2 is a perspective view of one embodiment of an articulating
arm assembly which is suitable for use as part of the manifold
assembly of FIG. 1;
FIG. 3 is a cross sectional view of the articulating arm assembly
of FIG. 2 shown mounted on a T connector;
FIG. 3A is an enlarged cross sectional view of an embodiment of the
seal assembly component of the articulating arm assembly of FIG.
3;
FIG. 4 is a cross sectional view of an embodiment of a riser swivel
seal arrangement which is suitable for use in the articulating arm
assembly of FIG. 3;
FIG. 5 is a cross sectional view of another embodiment of a riser
swivel seal arrangement which is suitable for use in the
articulating arm assembly of FIG. 3;
FIG. 6 is a cross sectional view of a second embodiment of an
articulating arm assembly which is suitable for use as part of the
manifold assembly of FIG. 1;
FIG. 7 is a cross sectional view of a third embodiment of an
articulating arm assembly which is suitable for use as part of the
manifold assembly of FIG. 1;
FIG. 7A is an enlarged cross sectional view of an embodiment of the
seal assembly component of the articulating arm assembly of FIG.
7;
FIG. 8 is a cross sectional view of another embodiment of an
articulating arm assembly which is suitable for use as part of the
manifold assembly of FIG. 1;
FIG. 9 is a cross sectional view of yet another embodiment of an
articulating arm assembly which is suitable for use as part of the
manifold assembly of FIG. 1; and
FIGS. 10-18 are cross sectional views of the cross connector
component of the articulating arm assembly of the present invention
showing alternative embodiments for mounting and orienting the
choke insert component of the invention.
DETAILED DESCRIPTION OF THE INVENTION
A manifold assembly in accordance with an illustrative embodiment
of the present invention is shown in FIGS. 1A and 1B. The manifold
assembly of this embodiment is shown mounted on an exemplary truck
trailer and will accordingly be referred to hereafter as a manifold
trailer. The manifold trailer, generally 10, may be used in the oil
and gas production industry to perform servicing operations on a
well. For example, in a well fracturing operation the manifold
trailer 10 may be used to inject a slurry into the wellbore in
order to fracture the hydrocarbon bearing formation and thereby
produce channels through which the oil or gas may flow. In this
operation the manifold trailer 10 connects a slurry source to a
number of high pressure pumping units and connects the high
pressure pumping units to a wellhead mounted at the top of the
wellbore. Thus, the manifold trailer eliminates the need to provide
separate connections between the slurry source and each high
pressure pumping unit and between each high pressure pumping unit
and the wellhead.
As shown in FIGS. 1A and 1B, the manifold trailer 10 comprises a
chassis 12 which is supported on a number of wheels 14 to allow the
manifold trailer to be towed between various locations. An intake
manifold assembly 16 is supported on the chassis 12 and includes
one or more (e.g., two as shown in FIG. 1B) longitudinally
extending intake pipes 18 which are fluidly connected at their
adjacent ends by transverse end pipes 20. Each end pipe 20 includes
a number of intake connectors 22 which are connectable to a slurry
source, such as a blender or storage tank (not shown), by
corresponding conduits (not shown). In addition, each intake pipe
18 includes a number of suction connectors 24 which are each
connectable to the suction side of a corresponding high pressure
pumping unit (not shown) by a respective conduit. Thus, the intake
manifold assembly 16 connects the slurry source to each of the high
pressure pumping units.
Referring still to FIGS. 1A and 1B, the manifold trailer 10 also
includes one or more (e.g., two as shown in FIG. 1B) longitudinally
extending main pipes or lines 26. One end of each main line 26 is
closed by a cap or plug 28, while the other end is provided with
one or more injection connectors 30 which are each connectable to a
corresponding wellhead (not show) by a respective conduit (not
shown). Each main line 26 comprises a number of straight pipe
sections and optional elbows (not shown) which are connected
together by T connectors 32. The branch of each T connector 32
defines a discharge connector 34 which is connectable to the
discharge side of a corresponding high pressure pumping unit by
means which will be described below. In the exemplary embodiment of
the invention shown in FIG. 1, each main line 26 comprises five T
connectors 32 and thus five discharge connectors 34. As a result,
each main line 26 is capable of connecting up to five high pressure
pumping units to a corresponding wellhead.
In accordance with the present invention, some or all of the
discharge connectors 34 are connected to corresponding high
pressure pumping units by respective articulating arm assemblies
36. In the embodiment of the invention shown in FIGS. 1A and 1B,
wherein each of the two main lines 26 is provided with five
discharge connectors 34, the manifold trailer 10 may comprise ten
arm assemblies 36, each of which connects an associated discharge
connector to the discharge side of a corresponding high pressure
pumping unit.
Referring to FIGS. 2 and 3, each arm assembly 36 includes a riser
swivel 38 which is connected to an isolation valve 40 that in turn
is connected to the T connector 32, a connector member, such as a
four-port cross connector 42, which is connected to the top of the
riser swivel, and an articulating conduit assembly which is
connected to the cross connector. The conduit assembly includes a
generally horizontal inner arm 44 which is connected to the cross
connector, a first swivel joint 46 which is connected to the distal
end of the inner arm, an outer arm 48 which is connected to the
distal end of the first swivel joint, a second swivel joint 50
which is connected to the distal end of the outer arm, and an end
connector 52 which is connected to the distal end of the second
swivel joint and is connectable to a pumping unit P.
As shown best in FIG. 3, the isolation valve 40 may comprise a
standard plug valve which includes a valve body 54 through which a
valve bore 56 extends, a closure member in the form of a plug
member 58 which includes a plug bore 60 that aligns with the valve
bore when the isolation valve is in the open position, a rotatable
stem 62 which is connected to the plug member, and an actuator 64
which is connected to the valve body over the stem. Alternatively,
a handwheel or other manual actuation device (not shown) may be
coupled to the stem instead of the actuator 64. In operation, the
actuator 64 rotates the stem 62 to thereby move the plug member 58
between the open position shown in FIG. 3 and a closed position in
which the plug bore 60 is offset from the valve bore 56. A suitable
isolation valve 40 for use with the present invention is the Model
3 inch 15 k ULT plug valve made by FMC Technologies, Inc. of
Houston, Tex.
Referring still to FIG. 3, the riser swivel 38 comprises a male
swivel part 66 through which a male swivel bore 68 extends and a
female swivel part 70 through which a female swivel bore 72
extends. The male swivel part 66 is received in the female swivel
part 70 and is rotatably connected thereto in a conventional
fashion, such as with a plurality of balls 74. At least one primary
seal member 76 is positioned between the male swivel part 66 and
the female swivel part 70 to thereby provide a continuous sealed
flow path between the male swivel bore 68 and the female swivel
bore 72.
Referring also to FIG. 4, the primary seal member 76, which is
shown positioned in an annular seal pocket 78 formed in the female
swivel part 70, may comprise a face type ring seal 80 having a
generally rectangular or slightly trapezoidal cross section and an
anti-extrusion ring 82 which is positioned in a corner of the ring
seal. The ring seal 80 and anti-extrusion ring 82 may be made of
any appropriate materials, such as nitrile elastomer and brass,
respectively. An example of a primary seal member 76 which is
suitable for use in the riser swivel 38 is the TripleStep Instream
packing made by FMC Technologies, Inc.
Referring still to FIG. 4, in addition to the first primary seal
member 76, the riser swivel 38 may be provided with a second
primary seal member 84. The second primary seal member 84, which
may be of the same construction as the first primary seal member
76, is positioned between the male swivel part 66 and the female
swivel part 70 downstream of the first primary seal member (where
the term "downstream" is in reference to a potential leak path from
the male and female swivel bores 68, 72 to the exterior of the
riser swivel 38). As shown in FIG. 4, the second primary seal
member 84 may be disposed in an annular seal pocket 86 which is
formed in the female swivel part 70. Alternatively, the second
primary seal member 84 may as shown in FIG. 5 be positioned in an
annular seal pocket 86' which is formed in the male swivel part
66.
The second primary seal member 84 ideally comprises the same or a
similar pressure rating as the first primary seal member 76.
Accordingly, the second primary seal member 84 will enable the
riser swivel 38 to remain in service under normal operating
conditions even if the first primary seal member 76 develops a
leak. In this regard, the operator may monitor the sealing
integrity of the first primary seal member 76 and, if a leak is
detected, continue operating the arm assembly 36 until a leak is
detected in the second primary seal member 84. Thus, the use of the
first primary seal 76 and the second primary seal 84 is superior to
the use in the prior art of a primary seal and a secondary or
backup seal since in the latter arrangement the secondary seal is
normally designed to retain pressure only temporarily until the
riser swivel can be removed from service if a leak is detected in
the primary seal.
The sealing integrity of the first primary seal member 76 may be
monitored through a first leak detection port 88 which extends to
between the first and second primary seal members 76, 84. Likewise,
the sealing integrity of the second primary seal member 84 may be
monitored through a second leak detection port 90 which extends to
between the second primary seal member 84 and the balls 74. The
second leak detection port 90 may also be used to inject a
corrosion inhibitor onto the second primary seal member 84. Also
shown in FIG. 4 are a number of conventional swivel components,
including a grease injection port 94 which is closed by a cap screw
96, an upper grease seal 98, a lower grease seal 100, and a ball
port 102.
Referring again to FIG. 3, the cross connector 42 may be connected
to the inner arm 44 and the inner arm may be connected to the first
swivel joint 46 by suitable first connectors 104. Also, the first
swivel joint 46 may be connected to the outer arm 48 and the outer
arm may be connected to the second swivel joint 50 by suitable
second connectors 106. In addition, the cross connector 42 may be
connected to the female swivel part 70 by a third connector 108,
the male swivel part 66 may be connected to the isolation valve 40
by a fourth connector 110, and the isolation valve may be connected
to the discharge connector 34 (which in this case is defined by the
branch of the T connector 32) by a fifth connector 112. Each of the
connectors 104 and 108-112 may comprise, for example, conventional
clamp-type connectors, while the second connectors 106 may
comprise, e.g., hammer unions.
Referring still to FIG. 3, the inner arm 44 is sealed to the cross
connector 42 by a first seal assembly 114, the cross connector is
sealed to the female swivel part 70 by a second seal assembly 116,
the male swivel part 66 is sealed to the isolation valve 40 by a
third seal assembly 118, and the isolation valve is sealed to the
discharge connector 34 (i.e., the branch of the T connector 32) by
a fourth seal assembly 120. In the embodiment of the invention
shown in FIG. 3, the seal assemblies at clamp locations 114-120 and
148 are identical. Therefore, these seal assemblies may be
described with reference to FIG. 3A, which is an enlarged view of
the second seal assembly 116. As shown in FIG. 3A, the second seal
assembly 116 comprises a bushing 122 which comprises a generally
rectangular cross section, a first ring seal 124 which is
positioned between the bushing and a recessed seal pocket 126 that
is formed in the cross connector 42, and a second ring seal 128
which is positioned between the bushing and a recessed seal pocket
130 that is formed in the female swivel part 70. The first and
second ring seals 124, 128 may comprise face-type ring seals
similar to the seal member 76 described above. The bushing 122 may
be made of any suitable material, such as alloy steel.
Referring again to FIG. 3, the cross connector 42 includes an inlet
port 132 which is fluidly connected to the inner arm 44, an outlet
port 134 which is fluidly connected to the female swivel bore 72, a
top port 136 and a side port 138. The top port 136 is closed by a
top plug 140 which is secured to the cross connector 42 by, e.g., a
wing union nut 142. In accordance with the present invention, the
top port 136 is located vertically above the inlet port 132, the
inner arm 44, the first swivel joint 46, the outer arm 48 and the
second swivel joint 50. As a result, the top port 136 provides the
highest access point to the flow bore extending through the arm
assembly 36. Thus, when the arm assembly 136 is being pressurized,
for example during hydrostatic pressure tests, the top plug 140 can
be opened to bleed off any air which may be trapped in the arm
assembly. In addition, the top port 136 provides access for
installation of a choke insert in the outlet port 134 without
having to disconnect the cross connector 42 from either the inner
arm 44 or the riser swivel 38.
The side port 138 is closed by a side plug 144 which is secured to
the cross connector 42 by, e.g., a clamp-type connector 146 and is
sealed to the cross connector by a side port seal assembly 148. In
accordance with the present invention, the side port 138 may
function as, e.g., an inspection port, a pump priming port, an
access for a horizontal choke insert and/or a flow cushioning
chamber.
Also, in one embodiment of the invention the cross connector 42 is
ideally configured so that the same or similar connectors may be
used for the connectors 104, 146 and the same or similar seal
assemblies may be used for the seal assemblies 114, 148. This will
enable the cross connector 42 to be oriented such that either the
inlet port 132 or the side port 138 is connected to the inner arm
44. In this manner, in the event the inlet port 132 reaches its
erosion limit, the cross connector 42 can be re-installed with the
side port 138 connected to the inner arm 44 to thereby
substantially extend the life of the cross connector.
A second embodiment of the arm assembly of the present invention is
shown in FIG. 6. The arm assembly of this embodiment, generally
150, is similar in many respects to the arm assembly 36 described
above. Therefore, only those features of the arm assembly 150 which
are different from those of the arm assembly 36 will be
described.
As shown in FIG. 6, the arm assembly 150 comprises a fixed orifice
choke insert 152 which is positioned in a counterbore 154 formed in
the outlet port 134 of the cross connector 42 and comprises a choke
orifice 156 that communicates with the inlet opening 132. The choke
insert 152 may be retained in position in the counterbore 154 by
any suitable means, such as a snap ring 158 which is received in a
corresponding groove formed in the counterbore above the choke
insert. The choke insert 152 may be removed and replaced through
the top port 136 of the cross connector 42 by simply removing the
top plug 140. Therefore, the cross connector 42 does not need to be
disconnected from the riser swivel 38 and/or the inner arm 44 in
order to replace the choke insert 152.
As is known in the art, the choke insert 152 acts to reduce the
pressure of the fluid flowing through the arm assembly 150 and to
dampen pressure pulsations in the main line 26. However, effecting
a desired pressure drop over a single choke insert 152 may result
in a high degree of erosion in portions of the arm assembly 150
located downstream of the choke insert.
In accordance with the present invention, the riser swivel 38 is
configured to produce an additional pressure drop downstream of the
choke insert 152. As a result of this arrangement, a larger orifice
choke insert 152 may be used and the erosion caused by a large
pressure drop over a single choke may accordingly be decreased. As
shown in FIG. 6, the riser swivel 38 is configured to produce the
second pressure drop by reducing the diameter of the female swivel
bore 72 and then gradually increasing the diameter of the male
swivel bore 68 until it is approximately the same as the diameter
of the plug bore 56. For example, the diameter of the female swivel
bore 72 may be approximately equal to the diameter of the choke
orifice 156 at the exit end of the choke insert 152, the diameter
of the upstream end of the male swivel bore 68 may be approximately
equal to the diameter of the female swivel bore, the diameter of
the downstream end of the male swivel bore may be approximately
equal to the diameter of the valve bore 56, and the diameter of the
male swivel bore may increase generally linearly from its upstream
end to its downstream end. In this manner, the desired pressure
drop will occur over the choke insert 152 and the male swivel bore
68.
A third embodiment of the arm assembly of the present invention is
shown in FIG. 7. The arm assembly of this embodiment, generally
160, comprises a fixed orifice choke insert 162 which is positioned
in the outlet port 134 of the cross connector 42 and includes a
choke orifice 164 which communicates with the inlet port 132 via a
number of inlet openings 166. The choke insert 162 extends to
approximately the top of the top port 136 and is therefore easily
accessible by simply removing the plug 140.
In this embodiment, the choke insert 162 supported on a seal
assembly 168 which is positioned between the cross connector 42 and
the female swivel part 70 and is retained in position by the plug
140. Referring to FIG. 7A, the seal assembly 168 is similar to the
seal assembly 116 described above in that it comprises a bushing
170, a first ring seal 172 which is engaged between the cross
connector 42 and the bushing, and a second ring seal 174 which is
engaged between the female swivel part 70 and the bushing. The
first and second ring seals 172, 174 may be similar to the ring
seals 124, 128 of the seal assembly 116, and the bushing 170 may be
made of the same material as the bushing 122. In this embodiment,
however, the bushing 170 comprises a preferably integral support
ring 176 which projects radially into the outlet port 134 and
thereby provides a support for the bottom of the choke insert
162.
As in the previous embodiment, the riser swivel 38 is configured to
produce a second pressure drop in the fluid flowing through the arm
assembly 160. As shown in FIG. 7, the riser swivel 38 is so
configured by reducing the diameter of the upstream end of the
female swivel bore 72 and then gradually increasing the diameter of
the female swivel bore until the diameter of the downstream end of
the female swivel bore is approximately the same as the diameter of
the male swivel bore 68. For example, the diameter of the upstream
end of the female swivel bore 72 may be approximately equal to the
diameter of the choke orifice 164 at the exit end of the choke
insert 162, the diameter of the downstream end of the female swivel
bore 72 may be approximately equal to the diameter of the male
swivel bore 68, and the diameter of the female swivel bore may
increase generally linearly from its upstream end to its downstream
end. In this manner, the desired pressure drop through the arm
assembly 160 will occur over the choke insert 162 and the female
swivel bore 72.
A fourth embodiment of the arm assembly of the present invention is
shown in FIG. 8. The arm assembly of this embodiment, generally
178, comprises a fixed orifice choke insert 180 which is positioned
in the outlet port 134 of the cross connector 42 and includes a
choke orifice 182 that communicates with the inlet opening 132 via
a single inlet opening 184. The choke insert 180 extends to
approximately the top of the top port 136 and includes a pull bar
186 which extends transversely across an upper end portion of the
choke insert to facilitate removal and orientation of the choke
insert.
In the embodiment of the invention shown in FIG. 8, the female
swivel bore 72 is configured as described above in connection with
FIG. 7 in order to produce a second pressure drop in the fluid
flowing through the arm assembly 178. In addition, the isolation
valve 140 is configured to produce a third pressure drop by
modifying the plug bore 60 to include a plug orifice 188. The plug
orifice 188 comprises a diameter smaller than the diameter of the
valve bore 56. In a preferred embodiment of the invention, the plug
orifice 188 comprises a diameter approximately equal to the
diameter of the choke orifice 182 at the exit end of the choke
insert 180. Thus, the desired pressure drop through the arm
assembly 178 will occur over the choke insert 180, the female
swivel bore 72 and the plug member 58. Moreover, the pressure drop
across the plug member 58 will reduce the erosion rate of the plug
member.
Another embodiment of the arm assembly of the present invention is
shown in FIG. 9. The arm assembly of this embodiment, generally
190, is similar to the arm assembly 178 discussed above. However,
in this embodiment the plug bore 60, the portion of the valve bore
56 located above the plug member 58, the male swivel bore 68 and
the female swivel bore 72 ideally all comprise approximately the
same diameter as the choke orifice 182 at the exit end of the choke
insert 180. This allows the use of a smaller primary seal member 76
for the riser swivel 38, which in turn reduces the hydrostatic
force acting between the male swivel part 66 and the female swivel
part 70. In addition, the second pressure drop across the arm
assembly 190 is produced by increasing the diameter of the portion
of the valve bore 56 located below the plug member 58 to match the
diameter of the T connector 32.
Several alternative features for the above-described embodiments
will now be described with reference to FIGS. 10-18.
In the embodiment shown in FIG. 10 the upper end of the choke
insert 180 is received in a recess 192 which is formed in the plug
140 and is secured thereto with a transverse pin 194. Thus, the
choke insert 180 may be removed from the cross connector 42 by
simply disconnecting the wing union nut 142 and removing the plug
140. The plug 140 may also be provided with a pressure test port
196.
In the embodiment shown in FIG. 11, the choke insert 180 is
positioned in the inlet port 132 of the cross connector with the
side opening 184 in alignment with the outlet port 134. The top or
left end (as viewed in FIG. 11) of the choke insert 180 extends
through the side port 138 and, as with the FIG. 10 embodiment, is
received in the recess 192 and secured to the plug 140 with the pin
194. In this embodiment, the bottom or right end of the choke
insert 180 is retained by a seal assembly 198 which is positioned
between the inner arm 44 and the cross connector 42. The seal
assembly 198, which is similar to the seal assembly 168 described
above, includes a bushing 170 having a support ring 176 which is
engaged by the bottom or right end of the choke insert 180.
The embodiment shown in FIG. 12 is similar to that shown in FIG.
10. However, in the FIG. 12 embodiment a locator pin 200 is
provided to aid in orienting the choke insert 180 relative to the
cross connector 42. In particular, the top of the locator pin 200
is received in a corresponding hole in the plug 140 and, when the
side opening 184 is aligned with the inlet port 132, the bottom end
of the locator pin is received in a corresponding hole in the cross
connector 42.
FIG. 13 illustrates another means for orienting the choke insert
180 relative to the inlet port 132 of the cross connector 42. In
this embodiment a locator pin 202 comprising a small diameter axial
projection 204 is positioned in the side port 138 of the cross
connector 42. When the side opening 184 is properly oriented with
the inlet port 132, the projection 204 is received in a
corresponding hole 206 in the choke insert 180. As with the
embodiment shown in FIG. 3, the side port 138 is closed by a plug
144 which is sealed to the cross connector with a seal assembly
148.
In the embodiment shown in FIG. 14, the choke insert 180 comprises
an upper flange which is trapped between a blind wing union nut 210
and an adjacent portion of the cross connector 42. An upper seal
212 is positioned between the upper flange 208 and the wing union
nut 210 and a lower seal 214 is positioned between the upper flange
and the cross connector 42. The upper and lower seals 212, 214 may
be similar to the seal member 76 described above. In addition, the
wing union nut 210 may comprise a vent port 216 to release trapped
pressure and a pressure test port 218.
The embodiment shown in FIG. 15 is similar to that shown in FIG.
14. However, in this embodiment the choke insert 180 is positioned
in the inlet port 132 with the side opening 184 in alignment with
the outlet port 134 and the flange 208 positioned at the opening of
the side port 138. In addition, the bottom or right end of the
choke insert 180 is retained by a seal assembly 220 similar to the
seal assembly 198 described above in connection with FIG. 11.
In the embodiment shown in FIG. 16, a blind plug 222 is provided
which extends into the top of the choke insert 180. The blind plug
222 includes a rim 224 which is secured against both the flange 208
of the choke insert 180 and an adjacent portion of the cross
connector 42 by a blind wing union nut 226. An inner seal 228 is
positioned between the blind plug 222 and the choke insert 228 and
an outer seal 230 is positioned between the choke insert and the
cross connector 42. The inner and outer seals 228, 230 may be
similar to the seal member 76 described above. In addition, and the
wing union nut 226 may include a vent port 232 to release trapped
pressure.
The embodiment shown in FIG. 17 is similar to that shown in FIG.
16; however, in this embodiment the choke insert 180 is positioned
in the inlet port 132 with the side opening 184 in alignment with
the outlet port 134 and the blind plug 222 positioned at the
opening of the side port 138. In addition, the bottom or right end
of the choke insert 180 is retained by a seal assembly 234 similar
to the seal assembly 198 described above in connection with FIG.
11.
In the embodiment shown in FIG. 18, the top port 136 is closed by a
plug 236 which is secured to the cross connector 42 by a wing union
nut 238. The plug 236 includes a reduced diameter bottom portion
240 which is received in the top of the choke insert 180 and is
secured thereto with a pin 242.
The manifold trailer 10 may be provided with means for supporting
the arm assemblies 36 on the chassis 12. Referring again to FIGS.
1A and 1B, for example, each lateral pair of arm assemblies 36 is
supported on the chassis 12 with a corresponding brace member 244.
Each brace member 244 includes a support 246 which is connected to
the chassis 12 (or another component which in turn is connected to
the chassis) by suitable means, such as welding, and a transverse
cross bar 248 which is connected to the top of the support. Each
end of the cross bar 248 is connected to a corresponding arm
assembly 36 with, for example, a collar 250 that is bolted to
either the female swivel part 70 or the portion of the cross
connector 42 through which the top port 136 extends. In addition, a
beam member 252 may be connected to successive cross bars 248 in
order to provide longitudinal stability to the brace members
244.
Thus, it may be seen that the arm assemblies 36 are connected to
and supported by the manifold trailer 10 at all times.
Consequently, separate conduit assemblies are not required to be
transported from location to location independently of the manifold
trailer 10. In addition, when setting up for well servicing
operations, separate conduit assemblies do not need to be connected
between the high pressure pumping units and the main lines 26.
Instead, with the manifold trailer 10 of the present invention the
main lines 26 can be connected to the high pressure pumping units
by simply extending the outer arm 48 of each arm assembly 36 to a
corresponding pumping unit.
Each arm assembly 36 may comprise means for supporting the inner
arm 44 in a generally horizontal position and for reducing the
bending and torsional loads acting on the connector 104 between the
inner arm and the first swivel joint 46. Referring to FIGS. 2 and
3, for example, each arm assembly 36 may comprise a diagonal brace
254 which extends between a collar 256 that is bolted or otherwise
connected to the female swivel part 70 and a sleeve 258 that is
bolted or otherwise connected to the inner arm 44. At least the
upper half of the sleeve 258 extends along the inner arm 44 and is
coupled to the first swivel joint 46 with a generally V-shaped
bracket 260. The bracket 260 includes a first end 262 which is
bolted or otherwise connected to the sleeve 258 and a second end
264 which is secured with a U bolt 266 or other suitable means to
the upper elbow 268 of the swivel joint 46. The second end 264
comprises a diagonal first plate 270 which includes a semi-circular
cutout that engages the underside of approximately the middle of
the elbow 268 and a horizontal second plate 272 which includes a
semi-circular cutout that engages the distal end portion of the
elbow. Thus, the brace 254 supports the inner arm 44 in a generally
horizontal position, while the bracket 260, and in particular the
engagement of the first and second plates 270, 272 with the elbow
266, transfers the bending and torsional loads acting on the first
swivel joint 46 to the inner arm 44, thereby preventing these loads
from acting on the connector 104, which could otherwise cause the
connector to become loose.
Each arm assembly 36 may also include means for counterbalancing
the weight of the outer arm 48 as it is being deployed. Referring
to FIG. 2, for example, each arm assembly 36 may include a
counterbalance hydraulic cylinder 274 which is secured between the
first swivel joint 46 and the outer arm 48. The cylinder 274 has a
first end which is rotatably connected to a bridge plate 276 that
is clamped or otherwise connected to the outer arm 48. The second
end of the cylinder 274 is rotatably connected to a generally
horizontally-extending bracket 278 that is clamped or otherwise
connected to the horizontal swivel part 280 of the first swivel
joint 46. The bracket 278 may be supported by a vertical plate 282
which is connected to the middle elbow 284 of the first swivel
joint 46 with a U bolt 286 or other suitable means. The cylinder
274 may comprise a simple fluid filled or spring cylinder.
Alternatively, cylinder 274 may comprise a hydraulic cylinder whose
pressure is controlled to provide a constant counterbalance force
to the outer arm 48.
It should be recognized that, while the present invention has been
described in relation to the preferred embodiments thereof, those
skilled in the art may develop a wide variation of structural and
operational details without departing from the principles of the
invention. For example, the various elements shown in the different
embodiments may be combined in a manner not illustrated above.
Therefore, the appended claims are to be construed to cover all
equivalents falling within the true scope and spirit of the
invention.
* * * * *